1. Technical Field
The present disclosure relates to a surgical apparatus, e.g., a surgical stapling apparatus. More particularly, the present disclosure relates to an endoscopic surgical stapling apparatus that includes a connecting feature for connecting the drive assembly of a loading unit, e.g., a single use loading unit (“SULU”) or disposable loading unit (“DLU”) onto the drive member or control rod of a surgical stapling apparatus, to ensure proper or complete engagement of the SULU or DLU, especially its drive assembly, to the surgical stapling apparatus. For simplicity, hereinafter, SULU or DLU will be referred to as “DLU”, but it should be understood to include either or both a DLU or SULU.
2. Background of Related Art
Surgical devices wherein tissue is first grasped or clamped between opposing jaw structure and then joined by surgical fasteners are well known in the art. In some instruments a knife is provided to cut the tissue which has been joined by the fasteners. The fasteners are typically in the form of surgical staples but two part polymeric fasteners can also be utilized.
Instruments for this purpose can include two elongated jaw members which are respectively used to capture or clamp tissue. Typically, one of the jaw members carries a staple cartridge which houses a plurality of staples arranged in at least two lateral rows while the other jaw member has an anvil that defines a surface for forming the staple legs as the staples are driven from the staple cartridge. Generally, the stapling operation is effected by cam members that travel longitudinally through the staple cartridge, with the cam members acting upon staple pushers to sequentially eject the staples from the staple cartridge. A knife can travel between the staple rows to longitudinally cut and/or open the stapled tissue between the rows of staples. Such instruments are disclosed, for example, in U.S. Pat. No. 3,079,606 and U.S. Pat. No. 3,490,675.
A later stapler disclosed in U.S. Pat. No. 3,499,591 also applies a double row of staples on each side of the incision. This patent discloses a surgical stapler that has a disposable loading unit in which a cam member moves through an elongate guide path between two sets of staggered staple carrying grooves. Staple drive members are located within the grooves and are positioned in such a manner so as to be contacted by the longitudinally moving cam member to effect ejection of the staples from the staple cartridge of the disposable loading unit. Other examples of such staplers are disclosed in U.S. Pat. Nos. 4,429,695 and 5,065,929.
Each of the instruments described above is designed for use in conventional surgical procedures wherein surgeons have direct manual access to the operative site. However, in endoscopic or laparoscopic procedures, surgery is performed through a small incision or through a narrow cannula inserted through small entrance wounds in the skin. In order to address the specific needs of endoscopic and/or laparoscopic surgical procedures, endoscopic surgical stapling devices have been developed and are disclosed in, for example, U.S. Pat. No. 5,040,715 (Green, et al.); U.S. Pat. No. 5,307,976 (Olson, et al.); U.S. Pat. No. 5,312,023 (Green, et al.); U.S. Pat. No. 5,318,221 (Green, et al.); U.S. Pat. No. 5,326,013 (Green, et al.); U.S. Pat. No. 5,332,142 (Robinson, et al.); and U.S. Pat. No. 6,241,139 (Milliman et al.), the entire contents of each of which are incorporated herein by reference.
Tyco Healthcare Group, LP, the assignee of the present application, has manufactured and marketed endoscopic stapling instruments, such as the Multifire ENDO GIA™ 30 and Multifire ENDO GIA™ 60 instruments, for a number of years. These instruments include a surgical stapling apparatus and a DLU. Typically, the DLU is attached to the apparatus immediately prior to surgery. After use, the DLU can be removed from the apparatus and a new DLU can be fastened to the apparatus to perform additional stapling and/or cutting operations. These instruments have provided significant clinical benefits. Nonetheless, improvements to these instruments are still possible.
It would be desirable to provide an improved DLU for a surgical stapling apparatus and an improved surgical stapling apparatus having the DLU loaded thereon.
It would also be desirable to provide a connecting feature for a DLU to assure proper loading of the DLU to the shaft of a surgical stapling apparatus.
Accordingly, it is an object of this disclosure to meet the aforementioned desires.
It is another object of this disclosure to provide a DLU with a connecting feature that provides a proper operative connection between the drive assembly of a DLU and the drive member of a surgical stapling apparatus.
It is another object of this disclosure to provide the above-mentioned DLU that provides such proper connection for a DLU that is already mounted to the apparatus without such a connection.
It is still another object of this disclosure to provide an improved DLU with a connecting feature that assures that if the DLU is not properly initially loaded to the shaft of the elongate body of a surgical stapling apparatus, in that the drive assembly of the DLU is not initially properly engaged by, coupled to or connected to a drive member of the surgical stapling apparatus, the locking or connecting feature nevertheless will assure proper connection of the drive assembly to the drive member and proper operation of the DLU and the surgical stapling apparatus. As one example, the DLU will undertake a proper connection at least during clamping of cartridge and anvil assemblies, and/or during firing of staples. As another example, after firing, the DLU will allow retraction of the drive assembly and opening of the cartridge assembly and/or anvil assembly.
Yet another object of the disclosure is to provide a DLU that, after firing and retraction, can be disconnected from the surgical stapling apparatus.
Still another object of the present disclosure is to provide the above objects in a roticulating, i.e., roticulable, DLU.